Mechanism of Deca-BDE-induced apoptosis in Neuro-2a cells: Role of death-receptor pathway and reactive oxygen species-mediated mitochondrial pathway

Decabromodiphenyl ether (BDE-209) is a prevalent polybrominated diphenyl ether (PBDE) congener known to have neurotoxicity. Effects of BDE-209 on Neuro-2a cells were performed in the present study and the possible apoptotic pathway was discussed. Results indicated that BDE-209 induced Neuro-2a cell apoptosis, increased the protein expression of Fas and Fas-associated death domain-containing protein (FADD) and activated the caspase-8 and -3 activities in a concentration-dependent manner, inferring the death-receptor pathway was involved in the apoptotic process. Meanwhile, BDE-209 exposure increased the Bax/Bcl-2 ratio and decreased the cellular mitochondrial membrane potential (MMP) which led to cytochrome C released to the cytoplasm. The intracellular caspase-9 was elevated simultaneously, which caused downstream caspase cascade and triggered cell apoptosis. Moreover, BDE-209 exposure increased cellular reactive oxygen species (ROS) level in a concentration-dependent manner and the addition of N-acetyl-l-cysteine (NAC), known as ROS scavengers, obviously reduced the apoptotic rate and a positive relationship was observed between the degree of apoptosis blocking and the loss of MMP and ROS production. We thus concluded that BDE-209 induced Neuro-2a cell apoptosis via the combination of the death-receptor signaling pathway and the mitochondrial signaling pathway. The elevated ROS production was considered to magnify the intracellular apoptosis signal and played a crucial role in apoptosis of Neuro-2a cells induced by BDE-209.     

超临界水氧化去除含酚废水TOC的动力学研究

本文利用自行设计的一套连续式超临界水氧化实验装置,以过氧化氢为氧化剂,处理实验室模拟含酚废水。在超临界条件下(P=30MPa,T=400℃,440℃,480℃,520℃)进行超临界水氧化实验。结果表明,TOC去除速率在氧化剂过量10倍的情况下,对TOC是2.15级反应。速率常数与温度的关系符合阿仑尼乌斯公式。反应的实验活化能为171.7kJ/mol,前置因子A为2.99×1011。     

Asn57 N-glycosylation promotes the degradation of hemicellulose by β-1,3–1,4-glucanase from Rhizopus homothallicus

Environmental Science and Pollution Research - N-glycosylation alters the properties of different enzymes in different ways. Rhizopus homothallicus was first described as an environmental isolate...     

Phytoremediation of the polluted Waigang River and general survey on variation of phytoplankton population

The Waigang River, a major tributary of the Qinhuai River system, has suffered from long-standing pollution because of lack of management. Restoration was commenced in April 2006 to reduce pollutants and improve water quality. Four ecological areas and ten surface carriers were constructed for the culture of plants (mainly water hyacinth (Eichhornia crassipes) and ryegrass (Lolium perenne L.)) for phytoremediation. Chemical oxygen demand (COD), total suspended solids (TSS), total phosphorus, total nitrogen (TN), ammonia?Cnitrogen (NH₃?CN), water transparency, and variations in phytoplankton population were investigated to evaluate the effects of restoration. Over 36?months, TSS, COD, TN, and NH₃?CN levels decreased by 91.1, 55.3, 91.5, and 86.5?%, respectively. Transparency increased from 25?cm in 2006 to 165?cm in 2009. Improvements in water quality significantly enhanced the diversity of phytoplankton, which were harmed by pollution stress. Our results show that the water hyacinth and ryegrass cultured in the ecological areas and the surface carriers can be used to restore other heavily polluted rivers with conditions similar to those of the Waigang River, especially in the initial stages of restoration.     

活性黄染料废水脱色动力研究

本文采用草酸铁法（UV/Fe（C2O4）33-/H2 O2）氧化活性黄染料废水,其动力学模型为拟一级动力学反应,反应速率常数分别为0.01084 s-1,通过动力学研究方法获得染料废水脱色反应的半衰期为68s;考察了pH值和反应温度的变化对氧化反应动力学的影响,初始pH值在3.0～4.0之间,对于草酸铁法羟自由基氧化脱...     

Synthesis and evaluation of cationic flocculant P(DAC-PAPTAC-AM) for flocculation of coal chemical wastewater

In this study, a high-efficiency cationic flocculant, P(DAC-MAPTAC-AM), was successfully prepared using UV-induced polymerization technology. The monomer Acrylamide (AM): Acryloxyethyl Trimethyl ammonium chloride (DAC): methacrylamido propyl trimethyl ammonium chloride (MAPTAC) ratio, monomer concentration, photoinitiator concentration, urea content, and cationic monomer DAC:MAPTAC ratio, light time, and power of high-pressure mercury lamp were studied. The characteristic groups, characteristic diffraction peaks, and characteristic proton peaks of P(DAC-MAPTAC-AM) were confirmed by fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), ¹H nuclear magnetic resonance spectrometer (¹H NMR), and scanning electron microscopy (SEM). The effects of dosage, pH value, and velocity gradient (G) value on the removal efficiencies of turbidity, COD, ammonia nitrogen, and total phenol by poly aluminum ferric chloride (PAFC), P(DAC-MAPTAC-AM), and PAFC/P(DAC-MAPTAC-AM) in the flocculation treatment of coal chemical wastewater were investigated. Results showed that the optimal conditions for the flocculation of coal chemical wastewater using P(DAC-MAPTAC-AM) alone are as follows: dosage of 8–12 mg/L, G value of 100–250 s ^? 1, and pH value of 4–8. The optimal dosage of PAFC is 90–150 mg/L with a pH of 2–12. The optimal dosage for PAFC/P(DAC-MAPTAC-AM) is as follows: PAFC dosage of 90–150 mg/L, P(DAC-MAPTAC-AM) dosage of 8–12 mg/L, and pH range of 2–6. When P(DAC-MAPTAC-AM) was used alone, the optimal removal efficiencies of turbidity, COD, ammonia nitrogen, and total phenol were 81.0%, 35.0%, 75.0%, and 80.3%, respectively. PAFC has good tolerance to wastewater pH and good pH buffering. Thus, the flocculation treatment of coal chemical wastewater using the PAFC/P(DAC-MAPTAC-AM) compound also exhibits excellent resistance and buffering capacity.     

环境影响评价中河流调查、监测方法的探讨

根据实际工作的经验，对中小河流水环境研究中的河段选择、断面布设、测量采样、污染源调查、化验分析等几个方面进行初步探讨分析。     

宁夏南部山区新修水平梯田耕地质量提升技术研究

本文针对宁南山区新修水平梯田水土流失和土壤肥力持续衰退的问题,从梯田培肥技术、耕作技术和管理措施3个方面研究总结了宁南山区新修水平梯田耕地质量提升关键技术,为提高宁南山区新修水平梯田生产力提供了技术保障.     

对叉车额定起重量的分析和探讨

本文对叉车的额定起重量和实际起重量之间的联系与区别进行了分析,指出了额定起重量只是供叉车设计使用的参数,建议不要将额定起重量标识在叉车铭牌上,叉车用户应按照载荷曲线图来确定操作时的实际起重量.